An industrial fluid system typically includes the flow of fluid through tubes, pipes, ducts, or other conduits (hereinafter, “pipes”) as well as through fluid control devices such as pumps, valves, orifices, heat exchangers, and the like. Fluid systems are found in many different industries such as the oil and gas industry, refining, food and beverage industry, chemical and petrochemical industry, pulp and paper industry, power generation, pharmaceutical industry, and water and wastewater treatment. The fluid within the fluid system may be a single phase fluid (e.g., gas, liquid or liquid/liquid mixture) and/or a multi-phase mixture (e.g. paper and pulp slurries or other solid/liquid mixtures). The multi-phase mixture may be a two-phase liquid/gas mixture, a solid/gas mixture or a solid/liquid mixture, gas entrained liquid or a three-phase mixture.
Operation of a fluid system often requires that various parameters of the fluid be monitored. The parameters may be used as feedback for quality control or may be used to detect problems or needed maintenance in the system. These parameters may include velocity and volumetric flow rate of the fluid, among others.
The ability to measure velocity and flow rate of a fluid within a pipe is an important aspect of any system or strategy design to optimize the performance of a fluid system, particularly in a fluid system based on saturated vapor/liquid mixtures. The industry recognizes this, and has been developing a wide variety of technologies to perform this measurement. These include probe based devices, sampling devices, venturis and ultrasonic devices. While these technologies may be effective, they are not without their drawbacks. For example, typical meters are invasive. That is, they are installed such that they are in contact with the fluid in the fluid system. As a result, installation or maintenance of the meter often requires at least a portion of the fluid system to be isolated.